The OP's advice is reasonable for pre product-market fit startups/businesses. You're adding a lot of risk for very little benefit if you go all in on a product

The OP's advice is reasonable for pre product-market fit startups/businesses. You're adding a lot of risk for very little benefit if you go all in on a product that doesn't exist yet or that customers don't want. Plus most people never ship anything, which this advice helps to fix.